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Characterization of the Minimal Catalytic Domain Within EIF2B: the Guanine-nucleotide Exchange Factor for Translation Initiation

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Journal EMBO J
Date 2002 Oct 3
PMID 12356745
Citations 52
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Abstract

For protein synthesis initiation in eukaryotes, eIF2B is the guanine-nucleotide exchange factor for eIF2. eIF2B is an essential multi-subunit factor and a major target for translational control in both yeast and mammalian cells. It was shown previously that the largest eIF2B subunit, eIF2Bepsilon, is the only single subunit with catalytic function. Here we report the results of a molecular dissection of the yeast epsilon subunit encoded by GCD6 in which we have identified the catalytic domain. By analysis of a series of N-terminal deletions in vitro we find that the smallest catalytically active fragment contains residues 518-712 (termed Gcd6p(518-712)). Further deletion to position 581 (Gcd6p(581-712)) results in loss of nucleotide exchange function, but eIF2-binding activity is retained. C- terminal deletion of only 61 residues (Gcd6p(1-651)) results in loss of both functions. Thus Gcd6p(518-712) contains two regions that together constitute the catalytic domain of eIF2B. Finally, we show that the catalytic domain can provide eIF2B biological function in vivo when elevated levels eIF2 and tRNA(i)(Met) are also present.

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References
1.
Christianson T, Sikorski R, Dante M, Shero J, Hieter P . Multifunctional yeast high-copy-number shuttle vectors. Gene. 1992; 110(1):119-22. DOI: 10.1016/0378-1119(92)90454-w. View

2.
CHERFILS J, Chardin P . GEFs: structural basis for their activation of small GTP-binding proteins. Trends Biochem Sci. 1999; 24(8):306-11. DOI: 10.1016/s0968-0004(99)01429-2. View

3.
Gomez E, Pavitt G . Identification of domains and residues within the epsilon subunit of eukaryotic translation initiation factor 2B (eIF2Bepsilon) required for guanine nucleotide exchange reveals a novel activation function promoted by eIF2B complex formation. Mol Cell Biol. 2000; 20(11):3965-76. PMC: 85753. DOI: 10.1128/MCB.20.11.3965-3976.2000. View

4.
Anthony T, Fabian J, Kimball S, Jefferson L . Identification of domains within the epsilon-subunit of the translation initiation factor eIF2B that are necessary for guanine nucleotide exchange activity and eIF2B holoprotein formation. Biochim Biophys Acta. 2000; 1492(1):56-62. DOI: 10.1016/s0167-4781(00)00062-2. View

5.
Paulin F, Campbell L, OBrien K, Loughlin J, Proud C . Eukaryotic translation initiation factor 5 (eIF5) acts as a classical GTPase-activator protein. Curr Biol. 2001; 11(1):55-9. DOI: 10.1016/s0960-9822(00)00025-7. View